Thanks for the history lesson, but nobody's talking about vintage chains. We're talking about a chain that someone would buy now to put on their 6 speed bike. They OP upgraded to 7 speed, but he would have used the same chain if he left it 6. And as anyone that Googles it will find out, 6-8 speed bikes use the same exact chain. I'm not sure anyone makes separate size chains for 6, 7, or 8 speeds, do they? Is there a 6 speed chain you can buy that is different than an 8 speed chain? I'm guessing no.